Commutator for electric motors



F. H. HARTZELL.

COMMUTATOR FOR ELECTRIC MOTORS.

APPLICATION FILED OCT. 23. I9I7.

1 ,1 1 0,9 1 4 Patented Mar. 28, 1922.

/ ATTORNEY FOREST H. HARTZELL, 01 DAYTON, OHIO.

OOHMUTATOR FOR ELECTRIC MOTORS.

Specification of Letters Patent.

Patented Mar. 28, 1922.

Application filed October 23, 1917. Serial in. 198,107.

To all whom it may concern:

to such use but the same mode of construction suitably modified as to proportion and relation of parts may be employed for larger motors or those of higher efiiciency.

The object of the invention is to improve the structure of commutators whereby they will not only be cheapened'in construction, but light motors for toy purposes will be more efiicient in operation, economical in manufacture, easily and quickly assembled, and unlikely to become short circuited or out of repair.

With the above primary and other incidental objects in view as will more fully appear in the specification, the invention consists' of the features of construction, the parts and combinations thereof, and the mode of operation, or their equivalents, as hereinafter described and set forth in the claims.

Referring to the drawings, Fig. l is a perspective view of the assembled motor commutator which forms the subject matter hereof. Fig. 2 is a transverse sectional view. Fig. 3 is a longitudinal sectional view on line 33 of Fig. 2. Fig. 4 is a plan view of the blank from which a contact is formed. Fig. 5 is a perspective view of the commutator contact formed from the blank shown in Fig. 4. Fig. 6 is an end elevation of an assembled commutator embodying a modification of the construction shown in the preceding figures.

Like parts are indicated by similar characters of reference throughout the several views.

In constructing the commutator there is employed a main body of insulating material which may consist of fiber, hard rubber, bakelite or other henolic condensation product, or some simi ar material of non-electro conductive material. This insulating body 1 may be formed integral or as a single con tinuous body but is preferably though not necessarily laminated or formed of a series of disks 2 arranged side by side andin contact one with the other in sufiicient number to build up the insulating body 1 of required extent. One advantage of constructing the insulating body of a series of disks or laminae 2 of such material as fiber or composition is that they may be formed by a stamping operation in a punch press. Such method of manufacture is extremely cheap and rapid. The disks 2 are formed with a central hole or opening 3 to receive the armature shaft and a second series of small holes 4 arranged in spaced relation and upon the periphery are formed a series of spaced teeth or tongues 5. Inasmuch as the disks 2 are all identical in size and arrangement of the openings and tongues, the openings 4 and tongues or teeth 5 register with those of the succeeding disks when assembled to form the insulating body 1. Positioned about the periphery of the insulating body 1 and separated by the tongues or teeth 5 are segmental contact plates 6 formed from sheet metal the blank being shaped as shown in i Fig. 4. As there shown the plate 6 is provided with oppositely disposed projecting fingers or tines 7 and also with a projecting tongue or finger 8 for the attachment of the armature windings. The blank shown in Fig. 4 in practice is shaped as indicated in the detail view Fig. 5. The armature winding connection 8 is bent upward to a position angular in relation with the plate 6 while the tines or fingers 7 are bent downward in the opposite dlrection. The plate itself is curved upon a radius to agree with the periphery of the insulating body 1. In assembling the device the plates 6 with their downturned tines or fingers 7 and upturned armature connection 8 are positioned about the insulating body 1 intermediate the succeeding rows of teeth or tongues 5. It will be understood that if the insulating body 1 is formed as an integral body instead of a series of laminae or disks a series of longi tudinally disposed ribs or beads upon the periphery of said integral body will correspond to the succession or row of registered teeth or tongues 5.

The plates 6 having been assembled about the periphery of the body 1 intermediate such rows of teeth or tongues 5, the downturned tines or fingers 7 thereof will extend in registry with the holes or openings 4. By means of a suitable staking or bending fixture or tool the ends of the fingers or tines 7 are 'inturned and clenched within the holes 40f the disks or the body 1 as shown in detail in Fig. 3. In Fig. 5 these fingers or'tines have also been shown inturned in their final form. In Fig. 6 there has been shown a modification of the construction heretofore described in which in lieu of tongues or teeth 5 upon the disks 2 or ribs or beads formed upon an integral insulatin body 1, such disks or integral insulating dy are longitudinal rooves or slots 9. Bars or strips of insu ating material such-as mica, fiber, hard rubber or other suitable nonconductive material are inserted within the slots 9 intermediate the succession of contact plates 6. After the assembly has been completed the surface of the commutator is turned or ground ofi, thereby equalizing the teeth or ribs 5 or the inserted insulating bars or strips 10 with the surfaces of the. ad'acent plates 6.

lVbile the commutator illustrated in the drawing has been shown provided with but six contact surfaces, it will be understood that any number of such contacts may be employed, either more or less than those shown in the drawings. The construction heretofore described provides a commutator of simple, economical and eflicient construction for the purpose for which it is designed.

From the above description it will be apparent that there is thus provided a device of the character described, the particular features of advantage before enumerated as desirable but which obviously is susceptible of modification in its form, proportion, detail construction or arrangement of parts, without departing from the principle involved or sacrificing any of its advantages.

While in order to comply with the statutes, the invention has been described in language more orcless specific as to certain structural features, it is to be understood that the invention is not limited to any specific details, but that the means and construction herein described comprise but one mode of putting the invention into effect, and the invention is therefore claimed broadly in formed with a series of' any of its possible forms or modifications within the scope of the appended claims.

Having thus described my invention, I claim 1 In a commutator of the character described, a core comprising a plurality of toothed discs arranged side by side, and a series of contact plates longitudinally disposed about the periphery of the core and insulated one from another by the projection of the periplheral teeth of the discs between the lates, t e discs being held in assembled reation and the contact plates in engagement therewith by clenching the ends of the plates over the terminal discs.

2. A peripheral face commutator, comprising a core, a plurality of contact plates arranged about the periphery of the core, and intermediate projections of insulation integral with the core upon the contact face of the commutator intermediate the contact plates, the ends of said plates being clenched upon the opposite ends of the core.

3 A commutator of the character described, a cylindrical body of insulating material peripherally grooved to form integral ribs of insulation upon the contact face of the commutator, contact plates located about the peripheral face of the cylindrical body intermediate said integral ribs, the ends of said plates being clenched over the ends of the body.

4. A commutator of the character dee' scribed comprising a series of discs of insulating material placed side by side and a series of contact plates longitudinally arranged in spaced relation about the periphery of the discs and having their ends inturned to hold the discs in assembled relation.

5. A commutator of. the character de scribed, includin a core, com risin a series of discs arrange side by si e an a series of contacts arranged about the periphe of the core and holding the discs in aselfibled relation.

In testimony whereof, I have hereunto set my hand this 17th day of October, A. D. 1917.

FOREST H. HARTZELL. Witnmes: I

J. G. Amzrommn, Ammo Mobhur. 

